Back when I was a kid, I used to send out the occasional baseball card to see if it would get signed. Back then was using Jack Smalling's Baseball Address list, and I probably got about 2/3 of the cards I sent returned with a signature. Then a handful of times since, I sent out a couple of items for signature (I can recall in particular David Robinson and Lenn Sakata), and never got a single return. I figured that was indicative of the attitude of the modern athlete, and pretty much gave up. I would occasionally read in Tuff Stuff magazine about the seemingly high success rates that people were getting, but didn't believe it was possible.
My recent collection was started in earnest in 2007. I had recently completed my Sports Illustrated collection consisting of every single issue published since I was born, so I was looking for something new to collect. I've always been a collector of something. So I decided to start sending out some of the duplicate Sports Illustrated issues I had out to see if they would get signed. At first, I just researched the internet and found addresses (usually their business address or foundation) that way. It was time consuming but interesting. I started sending out a few, and surpringly got some back. Had the first few not come back, I probably would have given up on the hobby. So those came back and I started sending out some more. By this time, I realized there had to be a better way to get addresses, so I purchased the Meiselman books and the membership to sportscollectors.net. Soon, all the duplicate Sports Illustrateds that I wanted to send out had been sent, so I decided to send out certain issues that I did not have duplicates of. I knew I was taking a risk, but by researching the signing habits of the people I was sending to, I only sent to ones who were known to be good signers [note: I have violated this policy on certain occasions and have been burned. Mainly because there was no data available on certain athletes I wanted to send to]. After a while, postage on sending out the magazines started running high (total cost to mail out an issue + return postage + shipping materials runs about $5 a magazine), so I had to limit how many I was sending. I decided that my policy should be to only have 25 magazines out at any given time. I would only send out a magazine when I got one back. An invaluable resource to my hobby is the Sports Illustrated site where they maintain a database of who's appeared on their covers.